Last updated: May 3, 2025
In Rio Negro, Brazil, being aware of the UV Index is essential for maintaining skin health and preventing sunburn. With a climate classified as Cfb, this region experiences varying UV levels throughout the day, peaking at a 6-7 around midday. Understanding these UV levels not only helps residents and visitors safeguard their skin from potential damage but also promotes smart outdoor activity planning. By staying informed about UV exposure risks, you can enjoy the beautiful outdoors of Rio Negro while protecting yourself from harmful effects of the sun.
The UV Index exhibits a dynamic pattern throughout the day, peaking sharply around midday. Starting off mild at 07:00 and 08:00 with a UV Index of 1, exposure remains minimal. However, as the sun climbs, the intensity increases significantly by 09:00, reaching 3, and continues to rise to a notable peak of 7 at 12:00 and 13:00. This indicates a need for sun protection during these hours. By 14:00, the UV Index begins to decline, falling to 5, and subsequently drops further, settling at 1 by 17:00 and finally reaching 0 by 18:00. In summary, the day's UV exposure highlights the importance of vigilance against UV radiation, particularly between 10:00 and 14:00 when the sun’s rays are at their strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 7 | high | 25 min |
| 14:00 | 5 | moderate | 30 min |
| 15:00 | 3 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, the UV Index shows significant seasonal variations, with extreme risk levels dominating from January to April and then again in September and November. The highest UV readings peak at 15 during the winter months and early spring, indicating a burn time of just 10 minutes. Following this period, there is a notable decrease in UV Index readings, dropping to a high risk level in June and July at 6, where burn times extend to 25 minutes. As August arrives, the index rises again to 9 in the very high category before reverting to extreme levels in the fall months. Given this data, it is crucial for both visitors and residents to exercise caution, particularly during high-risk months (January-April, September, November) by wearing protective clothing, sunscreen, and limiting sun exposure to mitigate harmful effects.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rio de Janeiro UVI | 15 | 14 | 13 | 10 | 7 | 6 | 7 | 9 | 11 | 12 | 13 | 15 |
| Rio Negro | 15 | 15 | 13 | 11 | 8 | 6 | 6 | 9 | 11 | 13 | 15 | 15 |
| Sao Paulo UVI | 16 | 15 | 12 | 11 | 8 | 6 | 7 | 9 | 11 | 13 | 14 | 15 |
| Belo Horizonte UVI | 17 | 16 | 14 | 12 | 9 | 7 | 8 | 10 | 12 | 13 | 14 | 16 |
| Salvador UVI | 14 | 14 | 14 | 13 | 10 | 9 | 9 | 12 | 12 | 15 | 15 | 14 |
| Fortaleza UVI | 14 | 14 | 15 | 15 | 13 | 11 | 11 | 12 | 13 | 13 | 13 | 13 |